Blood test may personalize chemo breaks for advanced colon cancer

This phase 3 trial tests whether monitoring tumor DNA in the blood (ctDNA) can help doctors decide when to reduce or change chemotherapy for people with advanced colorectal cancer that cannot be removed by surgery. About 408 participants will be randomly assigned to either standard care or a strategy where ctDNA levels after two cycles of chemo guide the next steps—such as taking a chemo break, switching to a milder maintenance therapy, or changing drugs entirely. The goal is to see if this personalized approach improves both survival and quality of life.